BUILD: fix travis-ci config to support coverity_scan

- the build matrix had to be hardcoded to pass the travis lint test

.travis.yml

@@ -1,6 +1,6 @@
 language: cpp
-compiler:
-  - gcc
+#compiler:
+#  - gcc
 #  - clang
 
 branches:
@@ -16,16 +16,23 @@ notifications:
     on_failure: always
 
 env:
-- BOINC_TYPE=libs
-- BOINC_TYPE=server
-- BOINC_TYPE=client
-#- BOINC_TYPE=manager
   global:
     # The next declaration is the encrypted COVERITY_SCAN_TOKEN, created
     #   via the "travis encrypt" command using the project repo's public key
     - secure: "Rd++Hyurnwd/tvjH0PX2seO3QUZ6WOf8bSB2ZkKPfZCU6+tXVMvloyog6Mlc7vl0m3WFAzw24MDtNLFBUktRsVXOkqDup1s6PdkwwcwG+5wAnydN+kXF9PcqKyOi0xJvl48Wji+r92Y9SCLzPnQGjZg70xHET22bDZHt2FsjP80="
+#- BOINC_TYPE=libs
+#- BOINC_TYPE=server
+#- BOINC_TYPE=client
+#- BOINC_TYPE=manager
 
 matrix:
+  include:
+    - compiler: "gcc"
+      env: BOINC_TYPE=libs
+    - compiler: "gcc"
+      env: BOINC_TYPE=server
+    - compiler: "gcc"
+      env: BOINC_TYPE=client
   fast_finish: true
 
 before_install: