Rename aead_chacha20_poly1305 to chachapoly

While the old name is explicit and aligned with the RFC, it's also very long,
so with the mbedtls_ prefix prepended we get a 31-char prefix to each
identifier, which quickly conflicts with our 80-column policy.

The new name is shorter, it's what a lot of people use when speaking about
that construction anyway, and hopefully should not introduce confusion at
it seems unlikely that variants other than 20/1305 be standardised in the
foreseeable future.
diff --git a/visualc/VS2010/mbedTLS.vcxproj b/visualc/VS2010/mbedTLS.vcxproj
index 802cce7..b04935a 100644
--- a/visualc/VS2010/mbedTLS.vcxproj
+++ b/visualc/VS2010/mbedTLS.vcxproj
@@ -158,6 +158,8 @@
     <ClInclude Include="..\..\include\mbedtls\camellia.h" />

     <ClInclude Include="..\..\include\mbedtls\ccm.h" />

     <ClInclude Include="..\..\include\mbedtls\certs.h" />

+    <ClInclude Include="..\..\include\mbedtls\chacha20.h" />
+    <ClInclude Include="..\..\include\mbedtls\chachapoly.h" />
     <ClInclude Include="..\..\include\mbedtls\check_config.h" />

     <ClInclude Include="..\..\include\mbedtls\cipher.h" />

     <ClInclude Include="..\..\include\mbedtls\cipher_internal.h" />

@@ -198,6 +200,7 @@
     <ClInclude Include="..\..\include\mbedtls\platform.h" />

     <ClInclude Include="..\..\include\mbedtls\platform_time.h" />

     <ClInclude Include="..\..\include\mbedtls\platform_util.h" />

+    <ClInclude Include="..\..\include\mbedtls\poly1305.h" />
     <ClInclude Include="..\..\include\mbedtls\ripemd160.h" />

     <ClInclude Include="..\..\include\mbedtls\rsa.h" />

     <ClInclude Include="..\..\include\mbedtls\rsa_internal.h" />

@@ -231,6 +234,8 @@
     <ClCompile Include="..\..\library\camellia.c" />

     <ClCompile Include="..\..\library\ccm.c" />

     <ClCompile Include="..\..\library\certs.c" />

+    <ClCompile Include="..\..\library\chacha20.c" />
+    <ClCompile Include="..\..\library\chachapoly.c" />
     <ClCompile Include="..\..\library\cipher.c" />

     <ClCompile Include="..\..\library\cipher_wrap.c" />

     <ClCompile Include="..\..\library\cmac.c" />

@@ -268,6 +273,7 @@
     <ClCompile Include="..\..\library\pkwrite.c" />

     <ClCompile Include="..\..\library\platform.c" />

     <ClCompile Include="..\..\library\platform_util.c" />

+    <ClCompile Include="..\..\library\poly1305.c" />
     <ClCompile Include="..\..\library\ripemd160.c" />

     <ClCompile Include="..\..\library\rsa.c" />

     <ClCompile Include="..\..\library\rsa_internal.c" />