Allow the equals sign in prebuild commands

README

@@ -171,7 +171,7 @@ configuration to the build. These are:
                    the compile about character encodings, you probably need this.
  prebuild=xxxx     Specifies a shell command (or commands - chain with &&) to run
                    before the build takes place - the only proviso being that you
-                   can't use , or = characters.
+                   can't use commas in the command.
  novcheck=yes      Don't check that the version name and code in the resulting apk
                    are correct by looking at the build output - assume the metadata
                    is correct. This takes away a useful level of sanity checking, and

common.py

@@ -106,8 +106,8 @@ def read_metadata(verbose=False):
                         thisbuild['vercode'] = parts[1]
                         thisbuild['commit'] = parts[2]
                         for p in parts[3:]:
-                            pp = p.split('=')
-                            thisbuild[pp[0]] = pp[1]
+                            pk, pv = p.split('=', 1)
+                            thisbuild[pk] = pv
                         thisinfo['builds'].append(thisbuild)
                     elif field == "Use Built":
                         if value == "Yes":