jenkins: add JAVA_MEM var

In order to give us some flexibility in deploying jenkins,
let's add a JAVA_MEM variable that can set how many
gb to use.

In order to make this useful, we need to remove the memory
settings from the defaul JAVA_OPTS var in the dockerfile.

JAVA_OPTS is then re-exported before the entrypoint with the
memory settings concatenated.

Signed-off-by: Kelley Spoon <kelley.spoon@linaro.org>
Change-Id: I4ab3fc37eea33c8711a7cfb008dc834294ef8a63
1 file changed