Get rid of dependency on Guava

Since I789f9aa589 removed usage of Guava's Optional, we only have
the dependency on Guava for the following simple utility methods:

  Strings.isNullOrEmpty
  MoreObjects.firstNonNull

Remove the dependency and instead provide own implementations
of those methods.

Change-Id: Iddcc20005004d37dae703fc0522c546a5212575c
2 files changed
tree: 579bdef4a1b8773ae25e191066945ed5b1001e77
  1. .buckconfig
  2. .gitignore
  3. BUCK
  4. LICENSE
  5. lib/
  6. pom.xml
  7. src/